You've got to do a bunch of patrolling and jobs at school to get the endgame stuff?
Have you done the graduation stuff?
(I have a suspicion that some of the events in the final version of the game can lock each other out if you complete them in an unexpected order. Like the social groups at school you can unlock with a positive reputation).
You don't ever need to patrol; I consider it a trap choice most of the time. The rewards are easier to achieve with less time investment elsewhere except in some specific character designs (like a jock-style Billy).
The social group missions may still interfere with one another because the bugs were never fully worked out, but they won't lock each other out. One of the group missions does require a specific club mission to be complete before it is offered (stolen chemicals). Starting the Pixie chain locks literally everything else out though and the other events are never freed. Once Billy is told about Pixie, all bathroom vignettes, social missions, and club missions cease forever.
To progress to the end-game stuff (i.e. Pixie as there isn't anything else), you need to complete 3 specific club missions (peeping toms in the cheerleader lockers, stolen chemicals, stolen exam) then wait a couple more weeks for it to start. Several more weeks go by before you have any input into it though. The Pixie chain still has a couple of points where it can get stuck. If you end up in a loop without a chance for player input, you can progress by going to the school cafeteria on Friday and "meet with friends" -- meeting with a clique does not count, it has to be the generic choice.